Reception device

ABSTRACT

The present invention relates to a reception device that can select an optimal component. The reception device includes a first reception unit that receives a video or audio component transmitted on a broadcast wave, a second reception unit that receives a video or audio component distributed via a network, and a control unit that controls the operation of each unit. The control unit selects the optimal video or audio component from a plurality of video and audio components that the reception device can receive.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of U.S. application Ser. No. 15/893,177, filedFeb. 9, 2019, which is a continuation of U.S. application Ser. No.15/038,516, filed May 23, 2016, which is a U.S. National PhaseApplication of International Application No. PCT/JP2014/080577, filedNov. 19, 2014, which is based on and claims priority to JapaneseApplication No. 2013-250117, filed Dec. 3, 2013.

TECHNICAL FIELD

The present invention relates to a reception device and, in particular,relates to a reception device that can select an optimal component.

BACKGROUND ART

Not only services using broadcast but also hybrid services incollaboration with communication has been introduced in the fields ofdigital broadcasting (for example, Patent Document 1). The components,such as a video component, an audio component, and a caption component,forming a service can be transmitted via broadcast or communication insuch hybrid services.

CITATION LIST

-   Patent Document 1: Japanese Patent Application Laid-Open No.    2011-66556

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

It is assumed that the introduction of hybrid services makes thestructure of the components forming a service complicated while enablingthe provision of various services. However, a technical scheme forselecting the optimal component for each service is not established.

In the light of the foregoing, the present invention facilitates theselection of the optimal component for each service.

Solutions to Problems

A reception device according to an aspect of the present inventionincludes: a first reception unit that receives a component transmittedon a broadcast wave; a second reception unit that receives a componentdistributed via a network; and a control unit that controls operation ofeach unit, wherein the control unit selects an optimal component from aplurality of components that the reception device is able to receive.

The reception device can be an independent device or an internal blockincluded in a device.

The reception device according to an aspect of the present inventionreceives a component transmitted on a broadcast wave, receives acomponent distributed via a network, and selects the optimal componentfrom a plurality of component candidates that can be received.

Effects of the Invention

According to an aspect of the present invention, an optimal componentcan be selected.

The effects of the present invention are not limited to the effectsdescribed herein, and can be any one of the effects described herein.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram of a component layer structure.

FIG. 2 is a diagram of an exemplary structure of signaling information.

FIG. 3 is a diagram of a specific example of component layers.

FIG. 4 is a diagram of an exemplary screen layout.

FIG. 5 is a diagram of a specific example of audio component layers.

FIG. 6 is a diagram of a specific example of audio component layers.

FIG. 7 is a diagram of a specific example of audio component layers.

FIG. 8 is a diagram of a specific example of audio component layers.

FIG. 9 is a diagram of the configuration of an embodiment of a broadcastcommunication system using the present invention.

FIG. 10 is a diagram of the configuration of an embodiment of atransmission device using the present invention.

FIG. 11 is a diagram of the configuration of an embodiment of adistribution server using the present invention.

FIG. 12 is a diagram of the configuration of an embodiment of areception device using the present invention.

FIG. 13 is an explanatory flowchart of a transmission process.

FIG. 14 is an explanatory flowchart of a distribution process.

FIG. 15 is an explanatory flowchart of a reception process.

FIG. 16 is a diagram of an exemplary configuration of a computer.

MODE FOR CARRYING OUT THE INVENTION

The embodiments of the present invention will be described hereinafterwith reference to the appended drawings. Note that the embodiments willbe described in the following order.

1. Component Structure

2. System Configuration

3. Flow of Process Performed in Each Device

4. Specific Example of Operation

5. Computer Configuration

1. Component Structure Component Layer Structure

FIG. 1 is a diagram of a component layer structure.

As illustrated in FIG. 1, each of a video component (Video), an audiocomponent (Audio), and a caption component (Caption) includes threelayers, a selective layer (Selective Layer), a composite layer(Composite Layer), and an adaptive layer (Adaptive Layer). In the layerstructure, the composite layer is placed as the upper layer of theadaptive layer, and the selective layer is placed as the upper layer ofthe composite layer. The details of each layer will be described inorder hereinafter.

Adaptive Layer

The adaptive layer will be described first. As illustrated in FIG. 1,one of circular symbols with different patterns indicates a componenttransmitted on a broadcast wave (Broadcast Component), and the othercircular symbol indicates a component distributed via a network(Broadband Component) on the adaptive layer that is the lowest layer.These components are distributed as so-called adaptive streaming, and aplurality of components at different bit rates is prepared. A broadcastcomponent is prepared for each category in the example of FIG. 1. Notethat, however, a plurality of broadcast components can be prepared.Furthermore, the classification of the video component, the audiocomponent, and the caption component is herein referred to as a category(CATEGORY).

A line that swings right and left on a dotted arc in the drawingfunctions as a switch in the adaptive layer. This selects a componentfrom the components. In other words, the adaptive layer is a layer fordynamically switching the components in accordance with the adaptivedetermination by the receiver in each of the component categories andcausing the components to function as a component. Note that, when thereis only a component, the component is constantly selected without theselection with the switch.

The transmission channel or bit rate of the components can be designatedas the attribute of the components to be adaptively selected in theadaptive layer. For example, broadcast or communication is designated asthe attribute value of the transmission channel. For example, 10 Mbps isdesignated as the bit rate. For example, an attribute about screenresolution or robustness of a physical layer (PHY) can be designated.Note that the attributes of the components to be adaptively selected areexamples and another attribute can be designated.

The attribute can be designated as described above. This enables thereceiver to implement adaptive streaming distribution by switching thecomponents and adaptively selecting the optimal component everypredetermined period (for example, every 10 seconds). Specifically, whenthe transmission channel of the component is only communication, thecomponent at the optimal bit rate can be selected in response to theoccupation of a reception buffer (for example, a reception buffer 421 tobe described below with reference to FIG. 12) in the receiver and theoccupation varies depending on the congestion of the communicationchannel.

Alternatively, when the transmission channel of the component includesalso broadcast in addition to communication, the selection between thecommunication component and the broadcast component can be determined inaccordance with the bit rate of the broadcast component. For example, itis assumed in this example that components at 1 Mbps, 2 Mbps, 5 Mbps, 10Mbps, and 20 Mbps are prepared as the components to be distributed viathe network, and only a component at 8 Mbps is prepared as the componentto be transmitted on a broadcast wave.

When the receiver can receive the communication components at 10 and 20Mbps, the bit rate is higher than the bit rate of the broadcastcomponent in this example. Thus, the receiver preferentially receivesthe communication components. When it is difficult to receive thecommunication components at 10 and 20 Mbps due to congestion and thereceiver can receive the communication component at 5 Mbps, the receivercan select the broadcast component at 8 Mbps that the receiver canstably receive instead of the communication components. Note that, whena plurality of broadcast components is prepared, for example, thevariations in Carrier/Noise (C/N) of the broadcast signal are measuredand the broadcast components can adaptively be switched in response tothe result from the measurement.

Composite Layer

The composite layer will be described next. As illustrated in FIG. 1,the components adaptively selected in the adaptive layer are synthesizedas a component in the composite layer that is the upper layer of theadaptive layer. In other words, the composite layer is a layer forcombining the components in a group of the components to be synthesized(hereinafter, referred to as a “composite component group”) and causingthe synthesized components to function as a component (synthesizedcomponent) in each component category. Note that, when there is only acomponent in a group of the components to be synthesized, thesynthesizing operation is unnecessary.

For example, “scalable”, “three-dimensional image (3D)”, “tile”,“layer”, and “mixing” can be designated as the attribute of thecomponents to be synthesized in the composite layer. Each of theattributes indicates a type of combination of the components, and anattribute value indicating the element of the combination can bedesignated.

The “scalable” is an attribute indicating that the component to besynthesized is a component encoded in scalable coding. “Base” or“Extended” is designated as the attribute value of the “scalable”attribute.

For example, in order to provide an image at 4K resolution, an encodedsignal (video component) corresponding to an image at 2K resolution forwhich “Base” is designated as the attribute value of the “scalable”attribute is transmitted on a broadcast wave. Meanwhile, an encodedimage signal (video component) corresponding to the difference betweenthe image at 4K resolution and the image at 2K resolution is distributedvia the network while “Extended” is designated as the attribute value ofthe “scalable” attribute. Thus, a receiver compatible with 4K resolutioncan synthesize the base stream (Base Stream) transmitted via broadcastand the extended stream (Extended Stream) transmitted via communication,and display the image at 4K resolution. On the other hand, a receiverthat is not compatible with 4K resolution displays the image at 2Kresolution using the base stream transmitted via broadcast.

The “3D” is an attribute indicating that the component to be synthesizedis a component for a 3D image. “Right” or “Left” is designated as theattribute value of the “3D” attribute. For example, the signal of aright-eye image (video component) for which “Right” is designated as theattribute value of the “3D” attribute is transmitted on a broadcastwave. Meanwhile, the signal of a left-eye image (video component) forwhich “Left” is designated as the attribute value of the “3D” attributeis distributed via the network. Thus, a receiver compatible with a 3Dimage can synthesize the right-eye image signal and the left-eye imagesignal, and display the 3D image.

The “tile” is an attribute indicating that the component to besynthesized is a tiled component. For example, “TileA1”, “TileA2”,“TileB1”, “TileB2”, . . . , or “TileC1”, “TileC2”, . . . are designatedas the attribute value of the “tile” attribute.

For example, the “TileA” of the “TileA1”, “TileA2”, . . . indicates thatthe type of the tiling is a type A. When the tiling type A is a schemein which two tiled images are arranged right and left and displayed, thesignal of the tiled image (video component) for which “TileA1” isdesignated as the attribute value of the “tile” attribute and which isto be arranged on the left side is transmitted on a broadcast wave, andthe signal of the tiled image (video component) for which “TileA2” isdesignated as the attribute value of the “tile” attribute and which isto be arranged on the right side is distributed via the network. Thus, areceiver compatible with tiling display can synthesize the left-tiledimage signal and the right-tiled image signal, and display an image inaccordance with the tiling type A.

Similarly, for example, when a tiling type B is a scheme in which fourtiled images are arranged two by two and displayed, the signals for thefour tiled images (video components) are transmitted via broadcast orcommunication. Thus, a receiver can synthesize the tiled images, anddisplay the two by two images in accordance with the tiling type B. Forexample, when a tiling type C is a scheme in which a plurality of tiledimages is arranged as a panoramic image (for example, 360 degrees) anddisplayed, the signals of the tiled images (video components) aretransmitted via broadcast or communication. Thus, a receiver cansynthesize the tiled image signals, and display the panoramic image inaccordance with the tiling type C. Note that the types A to C of thetiling schemes are examples, and another tiling scheme can be used.

The “layer” is an attribute indicating that the component to besynthesized is a component layer displayed as a layer. “Layer1”,“Layer2”, . . . are designated as the attribute value of the “layer”attribute, for example, in the layering order from the lowest layer. Forexample, the signal of the first-layer image (video component) for which“Layer1” is designated as the attribute value of the “layer” attributeis transmitted on a broadcast wave. Meanwhile, the signal of thesecond-layer image (video component) for which “Layer2” is designated asthe attribute value of the “layer” attribute is distributed via thenetwork. Thus, a receiver compatible with layer display can synthesizethe first-layer image signal and the second-layer image signal, anddisplay an image that the second-layer image is layered on thefirst-layer image.

The “mixing” is an attribute indicating that the component to besynthesized is a component to be mixed. For example, “Track1”, “Track2”,. . . are designated as the attribute value of the “mixing” attribute.For example, a voice track (audio component) for which “Track1” isdesignated as the attribute value of the “mixing” attribute istransmitted on a broadcast wave. Meanwhile, a voice track (audiocomponent) for which “Track2” is designated as the attribute value ofthe “mixing” attribute is distributed via the network. Thus, a receivercompatible with mixing can mix the voice track 1 and the voice track 2(for example, adjust the volume relative positions or the panningposition), and output the mixed voice.

Note that the attributes of the components to be synthesized in thecomposite layer and the attribute values are examples, and anotherattribute and another attribute value can be designated.

Selective Layer

The selective layer will be described last. As illustrated in FIG. 1, aline that swings right and left on a dotted arc in the drawing functionsas a switch, and a component is selected from a plurality of componentsin the selective layer that is the upper layer of the composite layerand the highest layer. In other words, the selective layer is a layerfor statically selecting one or a plurality of components in a group ofthe components to be statically selected (hereinafter, referred to as a“selective component group”) in each component category in accordancewith a predetermined selection method. A method in which the userselects the components or a method in which the receiver automaticallyselects the components in accordance with the throughput of the receiveror the information about the user's taste can be used as the selectionmethod.

For example, “view tag”, “language”, “required receiver throughput”,“view title”, or “purpose” can be designated as the attribute of thecomponents to be statically selected in the selective layer.

Specifically, the “view tag” is a tag for combining the differentcomponent categories included in a view. For example, when “1” isdesignated as the “view tag”, the video component, audio component, andcaption component to which ID “1” is added are selected across thecategories. Similarly, when “2” is designated as the “view tag”, thecomponents to which ID “2” is added are selected across the categories.Note that the component to which a view tag is not added is independentin each category.

For example, a language code is designated as the “language”. Forexample, a Graphical User Interface (GUI) screen corresponding to thelanguage code is displayed and the user selects the desired language.The throughput required to the receiver is designated as the “requiredreceiver throughput”. The required throughput can be designated, forexample, with a level value, or codec and resolution can be designatedin multiple dimensions. For example, when the required throughput isdesignated with a level value and a level 2 is designated as the levelvalue, only the receiver with a throughput at the level 2 or higher canbe used.

A title for selecting a view screen is designated as the “view title”.For example, the view title is displayed in a text format, and the userselects the desired view screen. The information about the purpose ofthe component, for example, the narration voice for the main voice isdesignated as the “purpose”.

Note that the attributes of the components to be statically selected inthe selective layer are examples and another attribute can be selected.Furthermore, not only an attribute is used as the attribute of thecomponents to be statically selected, and the combination of a pluralityof attributes can be used.

The attributes of the components to be statically selected can bedesignated as described above. Thus, the application running in areceiver can select the component in accordance with the attribute ofthe components to be statically selected. However, when there is only aselective component group, the selection is unnecessary and theselective component group is selected. For example, when the videocomponent, audio component, and caption component in the differentcategories are combined and grouped with a view tag, the components areselected in a unit of the group.

When the receiver selects a plurality of components from the videocomponents and caption components, a plurality of image and captionscreens is displayed. Alternatively, when the receiver selects aplurality of components only form the audio components, the voices aremixed (in Mixing) and are output.

A selective layer exists in each component category in the exemplarycomponent layer structure of FIG. 1. Note that, however, a plurality ofselective layers can exist in each component category. Furthermore, thevideo component, audio component, and caption component are described asthe components in the component layer structure of FIG. 1. However, asimilar layer structure can be used for another component included in aservice.

Exemplary Signaling Information Structure

FIG. 2 is a diagram of an exemplary structure of the signalinginformation (the control signal) for implementing the component layerstructure illustrated in FIG. 1. Note that FIG. 2 illustrates elementsand attributes and “@” is attached to the attribute. Each of theindented elements and attributes is designated for the upper element ofthe indented elements.

As illustrated in FIG. 2, the “topAttribute” attribute is an attributefor the final selection and is defined with m0 types (m0=1, . . . , m0).For example, the selection number and the selection determination aredefined as the “topAttribute” attribute. The total number of componentsto be selected is designated as the selection number. The selection bythe user or automatic selection by the receiver is selected as theselection determination.

The information about a selective component group that is the componentgroup to be statically selected is designated as the“SelectiveComponentGroup” element. The “SelectiveComponentGroup” elementis the upper element of the “CompositeComponentGroup” element. Note thatthe frequency of appearance of the “SelectiveComponentGroup” is n1(n1=1, . . . , n1).

The “selectiveAttribute” attribute indicates a plurality of attributesprescribed for the “SelectiveComponentGroup” element. The attribute ofthe components to be statically selected is prescribed with m1 types(m1=0, . . . , m1). For example, an individual attribute such as “viewtag”, “language”, “required receiver throughput”, “view title”, or“purpose” is prescribed as the attribute of the components to bestatically selected in the selective layer for the “selectiveAttribute”attribute.

The information about the composite component group that is a componentgroup to be synthesized is designated as the “CompositeComponentGroup”element. The “CompositeComponentGroup” element is the upper element ofthe “AdaptiveComponent” element. Note that the frequency of appearanceof the “CompositeComponentGroup” element is n2 (n2=1, . . . , n2).

The “compositeAttribute” attribute indicates a plurality of attributesprescribed for the “CompositeComponentGroup” element, and the attributeof the components to be synthesized is prescribed with m2 types (m2=0, .. . , m2). For example, an individual attribute such as “scalable”,“3D”, “tile”, “layer”, or “mixing” is prescribed as attribute of thecomponents to be synthesized in the composite layer for the“compositeAttribute” attribute. The attributes indicate a type ofcombination of the components, and the attribute values indicating theelements in the combination can be designated.

The information about the component to be adaptively selected isdesignated as the “AdaptiveComponent” element. Note that the frequencyof appearance of the “AdaptiveComponent” element is n3 (n3=1, . . . ,n3).

The “adaptiveAttrbute” attribute indicates a plurality of attributesprescribed for the “AdaptiveComponent” element and the attribute of thecomponents to be adaptively selected is prescribed with m3 types (m3=0,. . . , m3). For example, the transmission channel or bit rate of thecomponent is individually prescribed as the attribute of the componentsto be adaptively selected in the adaptive layer for the“adaptiveAttrbute” attribute. The ID of the component is designated asthe “componentId” attribute.

Note that the data structure of the signaling information forimplementing the component layer structure in FIG. 1 described withreference to FIG. 2 is an example, and another data structure can beused. The signaling information is written in a markup language such asExtensible Markup Language (XML).

Specific Example of the Component Layer

A specific example of the component layer will be described withreference to FIGS. 3 to 8.

In a specific example of the component layer in FIG. 3, the “scalable”is designated as the attribute of the components to be synthesized inthe video composite layer (Composite Layer). A base stream (“ScalableBase” in the drawing) is transmitted via broadcast and an extendedstream (“Scalable Extended” in the drawing) is transmitted viacommunication in the adaptive layer (Adaptive Layer) that is the lowerlayer of the Composite Layer. In this example, only a broadcast videocomponent to be adaptively selected is prepared as the base stream andthus the broadcast video component is constantly selected. On the otherhand, a plurality of communication video components to be adaptivelyselected is prepared as the extended stream, and thus the optimal videocomponent is adaptively selected from the communication video components(“Adaptive switching” in the drawing).

To provide an image at 4K resolution, the encoded image signal (videocomponent) at 2K resolution transmitted via broadcast, and the encodedimage signal (video component) corresponding to the difference betweenthe image at 4K resolution and the image at 2K resolution transmittedvia communication are synthesized in the video composite layer. When,for example, the “required receiver throughput” is designated as theattribute of the components to be statically selected in the selectivelayer (Selective Layer) and a receiver is compatible with 4K resolution,the receiver can display the synthesized image at 4K resolution (“4KCapable Main View” in the drawing). On the other hand, when the receiveris not compatible with 4K resolution, the receiver uses only the basestream transmitted via broadcast to display the image at 2K resolution(“4K Disable Main View” in the drawing). In other words, thecommunication video component is not used and thus the adaptiveselection of the video component is not performed in this case (“Nonswitching” in the drawing).

As illustrated in FIG. 4, the main view (Main View) means the maindisplay area in the display screen in this example. The image at 4Kresolution or 2K resolution is displayed on the main view. A sub-view(Sub View) that is an auxiliary display area relative to the maindisplay area can be displayed on the exemplary screen in FIG. 4. Asub-view 1 (“Sub View1” in the drawing) and a sub-view 2 (“Sub View2” inthe drawing) can be selected as the selective component group in theselective layer in the exemplary component layer in FIG. 3.

Only a communication video component is prepared for the sub-view 1 inthe adaptive layer. Thus, the adaptive selection is not performed andthe communication video component is constantly selected (“Nonswitching” in the drawing). A plurality of communication videocomponents to be adaptively selected is prepared for the sub-view 2 inthe adaptive layer, and thus the optimal communication video componentis adaptively selected from the communication video components asnecessary (“Adaptive switching” in the drawing). Although the sub-view 1is displayed together with the main view in the exemplary screen in FIG.4, the user can select which view, the main view, the sub-view 1, or thesub-view 2 is displayed, for example, using the GUI screen.

With reference to FIG. 3 again, the “scalable” is designated as theattribute of the components to be synthesized in the audio compositelayer (Composite Layer). A stereophonic stream is transmitted viabroadcast or communication (“Stereo” in the drawing) and a multi-channelstream (“Multi-channel Dev” in the drawing) is transmitted viacommunication in the adaptive layer (Adaptive Layer) that is the lowerlayer of the audio composite layer.

A plurality of audio components to be adaptively selected is prepared asthe stereophonic stream, and thus the optimal audio component isadaptively selected from the broadcast or communication audio components(“Adaptive switching” in the drawing) in this example. In other words,the audio component with a normal robustness (“Normal Robustness” in thedrawing) and the audio component with a high robustness (“HighRobustness” in the drawing) are prepared as the broadcast audiocomponents and one of the audio components can adaptively be selected.This enables the operation, for example, in which only the voice isoutput when the audio component with a high robustness is selected andit is difficult due to a reason to display the image on the receiver.When it is difficult to receive the broadcast audio component, thecommunication audio component can be selected.

On the other hand, only an audio component to be adaptively selected isprepared as the multi-channel stream, and thus the communication audiocomponent is constantly selected.

The stereophonic audio component transmitted via broadcast and themulti-channel audio component transmitted via communication aresynthesized and a synthesized 22.2 multi-channel component is generatedin the audio composite layer. When, for example, the “required receiverthroughput” is designated as the attribute of the components to bestatically selected in the selective layer (Selective Layer) and thereceiver is compatible with 22.2 multiple channels, the receiver canoutput the synthesized 22.2 multi-channel voice (“22.2ch Capable MainView” in the drawing). On the other hand, when the receiver is notcompatible with 22.2 multiple channels, the receiver outputs thestereophonic voice using only the stereophonic stream transmitted viabroadcast or communication (“22.2ch Disable Main View” in the drawing).

The view tag 1 is added to the audio components as the attribute of thecomponents to be statically selected in the audio selective layer inthis example. The audio components cooperate with the video componentsto which the view tag 1 is similarly added in the video selective layer.In other words, the voice corresponding to the audio components isoutput for the image displayed on the main view of the exemplary screenin FIG. 4.

The audio component to which the view tag 2 is added as the attribute ofthe components to be statically selected in the selective layercooperates with the video component to which the view tag 2 is similarlyadded in the video selective layer (“Sub View1” in the drawing). Inother words, the voice corresponding to the audio components is outputfor the image displayed on the sub-view 1 of the exemplary screen inFIG. 4.

The audio component to which the view tag 3 is added as the attribute ofthe components to be statically selected in the selective layercooperates with the video component to which the view tag 3 is similarlyadded in the video selective layer (“Sub View2” in the drawing). Notethat only a communication audio component is prepared for each of theaudio sub-view 1 and the audio sub-view 2 in the adaptive layer. Thus,the adaptive selection is not performed, and the communication audiocomponent is constantly selected.

As illustrated in FIG. 3, the synthesis of the caption components is notperformed in the caption composite layer (Composite Layer) and theadaptive selection of the caption components is also not performed inthe adaptive layer (Adaptive Layer). Thus, the caption components in theselective layer (Selective Layer) and the caption components in theadaptive layer correspond, respectively, one by one. Note that only theleftmost caption component among the caption components in the drawingsis transmitted via broadcast, and the other caption components aretransmitted via communication.

The caption components to which the view tag 1 is added as the attributeof the components to be statically selected in the selective layercooperate with the video components and audio components to which theview tag 1 is similarly added. Specifically, the English caption and theSpanish caption are provided in this example. Not only the main captions(“Eng(Nor)” and “Spa(Nor)” in the drawing) but also more detailedexplanatory captions (“Eng(Ex)” and “Spa(Ex)” in the drawing) areprepared for the captions. When “language” is designated as theattribute of the components to be statically selected in the captionselective layer by the user's selection, the caption in accordance with,for example, the language code of the selected language can bedisplayed. In other words, the caption of English or Spanish selected bythe user is superimposed and displayed on the image displayed on themain view of the exemplary screen in FIG. 4.

The caption components to which the view tag 2 is added as the attributeof the components to be statically selected in the selective layercooperate with the video component and audio component to which the viewtag 2 is similarly added. Specifically, the English caption (“Eng” inthe drawing) and the Spanish caption (“Spa” in the drawing) areprepared. Thus, the caption in response to the user's selection can besuperimposed and displayed on the image displayed on the sub-view 1 ofthe exemplary screen in FIG. 4.

The caption components to which the view tag 3 is added as the attributeof the components to be statically selected in the selective layercooperate with the video component and audio component to which the viewtag 3 is similarly added. Specifically, the English caption (“Eng” inthe drawing) and the Spanish caption (“Spa” in the drawing) areprepared. Thus, the caption in response to the user's selection can besuperimposed and displayed on an image.

Another Specific Example of the Audio Component Layer

Another specific example of the audio component layer will be describednext with reference to FIGS. 5 to 8.

As illustrated in FIG. 5, for example, a complete version (“CompleteMain” in the drawing) or a mixed version (“Tracks to be Mixed” in thedrawing) can be designated as the attribute value in the audio selectivelayer (Selective Layer).

Thus, for example, when the complete version is designated as theattribute value, a complete audio component is provided and the voicecorresponding to the audio component is output. Note that a broadcastaudio component at a high bit rate and a communication audio componentat a low bit rate are prepared as the complete audio stream so that theoptimal audio component is adaptively selected (“Adaptive switching” inthe drawing).

Alternatively, for example, when the mixed version is designated as theattribute value, a music component (“Music” in the drawing), a dialogcomponent (“Dialog” in the drawing), and an effect component (“Effect”in the drawing) are provided and synthesized so that the voicecorresponding to the synthesized component is output. Note that thecommunication audio components at high and low bit rates are prepared asthe music stream so that the optimal audio component is adaptivelyselected (“Adaptive switching” in the drawing).

Note that only a plurality of audio components for the mixed version canbe provided without providing an audio component for the completeversion as illustrated in FIGS. 6 and 7. In this example, a plurality ofcomponents at different bit rates can be prepared not only for the musicstream but also for the dialog stream or the effect stream so that theoptimal component can adaptively be selected.

As illustrated in FIG. 8, for example, the English version (“Main EngAudio” in the drawing) or the Spanish version (“Main Spa Audio” in thedrawing) can be designated as the attribute value of the “language”attribute in the audio selective layer (SELECTIVE LAYER).

Thus, for example, when the English version is designated as theattribute value, the dialog component (“Dialog” in the drawing), theeffect component (“Effect” in the drawing), and the music component(“Music” in the drawing) are provided and synthesized so that theEnglish voice corresponding to the synthesized component is output. Notethat the broadcast component at a high bit rate and the communicationcomponent at a low bit rate are prepared as the dialog stream so thatthe optimal component is adaptively selected (“Adaptive switching” inthe drawing). The communication components at high and low bit rates areprepared for the music stream so that the optimal component isadaptively selected (“Adaptive switching” in the drawing).

For example, when the Spanish version is designated as the attributevalue, only an audio component is prepared as the audio stream for theSpanish version. Thus, the audio component is provided and the Spanishvoice is output.

2. System Configuration Configuration of the Broadcast CommunicationSystem

FIG. 9 is a diagram of the configuration of an embodiment of thebroadcast communication system using the present invention.

As illustrated in FIG. 9, a broadcast communication system 1 includes adata providing server 10, a transmission device 20, a distributionserver 30, and a reception device 40. The distribution server 30 and thereception device 40 are connected to each other via a network 90 such asthe Internet.

The data providing server 10 provides various components such as a videocomponent, an audio component, and a caption component to thetransmission device 20 and the distribution server 30. In this example,the data providing server 10 provides a video component at 8 Mbps to thetransmission device 20, and video components at 1 Mbps, 2 Mbps, 5 Mbps,10 Mbps, and 20 Mbps to the distribution server 30, respectively, as thecomponents forming a television program in order to implement adaptivestreaming distribution in a service, for example, providing thetelevision program.

The transmission device 20 transmits the various components providedfrom the data providing server 10 (for example, the video component at 8Mbps) using a broadcast wave of digital broadcasting. The transmissiondevice 20 transmits also the control signal (the signaling informationin FIG. 2) together with the component using a broadcast wave of digitalbroadcasting. Note that the control signal (the signaling information inFIG. 2) can be distributed, for example, from a dedicated serverconnected to the network 90.

The distribution server 30 distributes various components provided fromthe data providing server 10 (for example, the video components at 1Mbps, 2 Mbps, 5 Mbps, 10 Mbps, and 20 Mbps) to the reception device 40via the network 90 in response to the request from the reception device40.

The reception device 40 receives the broadcast signal transmitted fromthe transmission device 20 and obtains the control signal (the signalinginformation in FIG. 2). The reception device 40 obtains variouscomponents such as a video component, an audio component, and a captioncomponent transmitted from the transmission device 20 (for example, thevideo component at 8 Mbps) in accordance with the control signal. Thereception device 40 obtains various components such as a videocomponent, an audio component, and a caption component distributed fromthe distribution server 30 (for example, the video components at 1 Mbps,2 Mbps, 5 Mbps, 10 Mbps, and 20 Mbps) in accordance with the controlsignal.

The reception device 40 displays the image of the video component andthe caption component on the display, and outputs the voice of the audiocomponent in synchronization with the image from a loudspeaker. In thisexample, the optimal video component is adaptively selected and switchedamong the broadcast video component at 8 Mbps, and the communicationvideo components at 1 Mbps, 2 Mbps, 5 Mbps, 10 Mbps, and 20 Mbps, forexample, every predetermined period (for example, every 10 seconds).This implements the adaptive streaming distribution.

Note that the reception device 40 can be a single device including adisplay and a loudspeaker, or can be embedded, for example, in atelevision receiver or a video recorder.

The broadcast communication system 1 has the configuration describedabove. The detailed configuration of each device included in thebroadcast communication system 1 in FIG. 9 will be described next.

Configuration of the Transmission Device

FIG. 10 is a diagram of the configuration of an embodiment of thetransmission device using the present invention.

As illustrated in FIG. 10, the transmission device 20 includes acomponent obtaining unit 201, a control signal obtaining unit 202, anMux 203, and a transmission unit 204.

The component obtaining unit 201 obtains various components from thedata providing server 10 and provides the components to the Mux 203.

The control signal obtaining unit 202 obtains the control signal (thesignaling information in FIG. 2) from an external server such as thedata providing server 10 or a built-in storage and provides the controlsignal to the Mux 203.

The Mux 203 multiplexes the various components from the componentobtaining unit 201 and the control signal from the control signalobtaining unit 202 to generate a transport stream and provides thetransport stream to the transmission unit 204.

The transmission unit 204 transmits the transport stream provided fromthe Mux 203 as a broadcast signal to the antenna 205.

Configuration of the Distribution Server

FIG. 11 is a diagram of the configuration of an embodiment of thedistribution server using the present invention.

As illustrated in FIG. 11, the distribution server 30 includes a controlunit 301, a component obtaining unit 302, an accumulation unit 303, anda communication unit 304.

The control unit 301 controls the operation of each unit in thedistribution server 30.

The component obtaining unit 302 obtains various components from thedata providing server 10 and provides the components to the control unit301. The control unit 301 accumulates the various components from thecomponent obtaining unit 302 in the accumulation unit 303. Thus, thevarious components from the data providing server 10 accumulate in theaccumulation unit 303.

The communication unit 304 exchanges various types of data with thereception device 40 via the network 90 in accordance with the control bythe control unit 301.

When the communication unit 304 receives a request for distribution of astream (component) from the reception device 40, the control unit 301reads the requested component from the accumulation unit 303. Thecontrol unit 301 controls the communication unit 304 to distribute thestream including the component read from the accumulation unit 303 tothe reception device 40 via the network 90.

Configuration of the Reception Device

FIG. 12 is a diagram of the configuration of an embodiment of thereception device using the present invention.

As illustrated in FIG. 12, the reception device 40 includes a tuner 402,a Demux 403, a selection and synthesis unit 404, a selection andsynthesis unit 405, a selection and synthesis unit 406, a control unit407, an NVRAM 408, an input unit 409, a communication unit 410, a Demux411, a video decoder 412, a video output unit 413, an audio decoder 414,an audio output unit 415, and a caption decoder 416.

The tuner 402 extracts the broadcast signal on the channel of theselected service from the broadcast signals received from the antenna401 to demodulate the extracted signal, and provides a transport streamobtained from the demodulated signal to the Demux 403.

The Demux 403 separates the transport stream provided from the tuner 402into the components and the control signal, and provides the componentsto the selection and synthesis units 404 to 406 and provides the controlsignal to the control unit 407. In this example, the components areseparated into a video component, an audio component, and a captioncomponent and are provided to the selection and synthesis unit 404, theselection and synthesis unit 405, and the selection and synthesis unit406, respectively.

The control unit 407 controls the operation of each unit in thereception device 40. The NVRAM 408 is a non-volatile memory, and recordsvarious types of data in accordance with the control by the control unit407. The control unit 407 controls the selection and synthesis processperformed by the selection and synthesis units 404 to 406 in accordancewith the control signal (the signaling information in FIG. 2) providedfrom the Demux 403.

The input unit 409 provides an operation signal corresponding to theuser operation to the control unit 407. The control unit 407 controlsthe operation of each unit in the reception device 40 in accordance withthe operation signal from the input unit 409.

The communication unit 410 exchanges various types of data with thedistribution server 30 via the network 90 in accordance with the controlby the control unit 407. The communication unit 410 provides the streamreceived from the distribution server 30 to the Demux 411. At that time,the communication unit 410 receives the stream distributed from thedistribution server 30 while buffering the stream data in a receptionbuffer 421 provided in the communication unit 410.

The Demux 411 separates the stream provided from the communication unit410 into components and provides the separated components to theselection and synthesis units 404 to 406. In this example, the videocomponent is provided to the selection and synthesis unit 404, the audiocomponent is provided to the selection and synthesis unit 405, and thecaption component is provided to the selection and synthesis unit 406,respectively, after the stream is separated into the components.

The selection and synthesis unit 404 selects and synthesizes the videocomponent from the Demux 403 and the video component from the Demux 411in a selection and synthesis process (for example, the process performedin each layer of the video component layers in FIG. 1) in accordancewith the control by the control unit 407. Then, the selection andsynthesis unit 404 provides the video component obtained from theprocess to the video decoder 412.

The video decoder 412 decodes the video component provided from theselection and synthesis unit 404, and provides the video data obtainedfrom the decoding to the video output unit 413. The video output unit413 outputs the video data provided from the video decoder 412 to thedownstream display (not illustrated). This output displays, for example,the image of a television program on the display.

The selection and synthesis unit 405 selects and synthesizes the audiocomponent from the Demux 403 and the audio component from the Demux 411in a selection and synthesis process (for example, the process performedin each layer of the audio component layers in FIG. 1) in accordancewith the control by the control unit 407. Then, the selection andsynthesis unit 405 provides the audio component obtained from theprocess to the audio decoder 414.

The audio decoder 414 decodes the audio component provided from theselection and synthesis unit 405, and provides the audio data obtainedfrom the decoding to the audio output unit 415. The audio output unit415 outputs the audio data provided from the audio decoder 414 to thedownstream loudspeaker (not illustrated). This outputs the voice, forexample, corresponding to the image of a television program from theloudspeaker.

The selection and synthesis unit 406 selects and synthesizes the captioncomponent from the Demux 403 and the caption component from the Demux411 in a selection and synthesis process (for example, the processperformed in each layer of the caption component layers in FIG. 1) inaccordance with the control by the control unit 407. Then, the selectionand synthesis unit 406 provides the caption component obtained from theprocess to the caption decoder 416.

The caption decoder 416 decodes the caption component provided from theselection and synthesis unit 406, and provides the caption data obtainedfrom the decoding to the video output unit 413. When the caption decoder416 provides the caption data to the video output unit 413, the videooutput unit 413 synthesizes the caption data with the video data fromthe video decoder 412 and provides the synthesized data to thedownstream display (not illustrated). This displays the captioncorresponding to the image of a television program together with theimage on the display.

The selection and synthesis units 404 to 406 are provided on theupstream side of each decoder in the reception device 40 in FIG. 12 forthe sake of description. Note that, however, the selection and synthesisunits 404 to 406 can be provided on the downstream side of each decoderdepending on the contents of the selection and synthesis process.

3. The Flow of the Process that Each Device Performs

The flow of the process that each device included in the broadcastcommunication system 1 in FIG. 9 performs will be described next withreference to the flowcharts in FIGS. 13 to 15.

Transmission Process

The transmission process that the transmission device 20 in FIG. 9performs will be described with reference to the flowchart in FIG. 13.

In step S201, the component obtaining unit 201 obtains variouscomponents from the data providing server 10 and provides the componentsto the Mux 203.

In step S202, the control signal obtaining unit 202 obtains the controlsignal (the signaling information in FIG. 2), for example, from anexternal server and provides the control signal to the Mux 203.

In step S203, the Mux 203 multiplexes the various components from thecomponent obtaining unit 201 and the control signal from the controlsignal obtaining unit 202 to generate a transport stream, and providesthe transport stream to the transmission unit 204.

In step S204, the transmission unit 204 transmits the transport streamprovided from the Mux 203 as a broadcast signal via the antenna 205.When the process in step S204 is completed, the transmission process inFIG. 13 is completed.

The transmission process has been described above. In the transmissionprocess, the various components provided from the data providing server10 and the control signal are transmitted on a broadcast wave.

Distribution Process

The distribution process that the distribution server 30 in FIG. 9performs will be described with reference to the flowchart in FIG. 14.Note that it is assumed that the various components provided from thedata providing server 10 previously accumulate in the accumulation unit303 of the distribution server 30.

In step S301, the control unit 301 constantly monitors the communicationunit 304 to determine whether the reception device 40 requests acomponent via the network 90. The request of a component from thereception device 40 is waited in step S301 and the process goes to stepS302.

In step S302, the control unit 301 reads the component requested by thereception device 40 from the accumulation unit 303.

In step S303, the control unit 301 controls the communication unit 304to distribute the component (stream) read from the accumulation unit 303via the network 90 to the reception device 40. When the process in stepS303 is completed, the distribution process in FIG. 14 is completed.

The distribution process has been described above. In the distributionprocess, the various components (streams) provided from the dataproviding server 10 are distributed via the network 90 in response tothe request from the reception device 40.

Reception Process

The reception process that the reception device 40 in FIG. 9 performswill be described with reference to the flowchart in FIG. 15. Thereception process is performed, for example, when the user starts thereception device 40 by operating a remote controller and instructschannel selection.

In step S401, the tuner 402 receives broadcast signals via the antenna401 to extract the broadcast signal on the channel of the selectedservice from the received broadcast signals and demodulate the extractedsignal. The Demux 403 separates the transport stream from the tuner 402into the components and the control signal.

In step S402, the control unit 407 selects the optimal component fromthe component candidates in accordance with the control signal (thesignaling information in FIG. 2) from the Demux 403.

Specifically, the control unit 407 obtains the signaling information inFIG. 2 as the control signal, and thus first recognizes the number ofcomponents to be selected based on the “topAttribute” attribute amongthe candidates. Then, the control unit 407 controls the operation inaccordance with the selection determination.

For example, when the user selects the components, the control unit 407displays the information designated as the attribute of the componentsto be statically selected for each selective component group on theselective layer that is the highest layer with a GUI screen so that theuser selects the selective component group (the components). Forexample, when the receiver automatically selects the components, thecontrol unit 407 selects the selective component group (the components)in accordance with the information designated as the attribute of thecomponents to be statically selected for each selective component groupon the selective layer that is the highest layer.

The component selection process is basically performed per category suchas the video component category, or the audio component category.However, when a view tag is designated as the attribute of thecomponents to be statically selected, the selective component group (thecomponents) is selected across the categories.

Next, when there is a plurality of “CompositeComponentGroup” elements inthe selected selective component group (the components), the controlunit 407 selects the components, which are to be synthesized inaccordance with the designated attribute in the composite layer, fromthe components to be adaptively selected in the adaptive layer that isthe lower layer of the composite layer. The control unit 407 controlsthe selection and synthesis units 404 to 406 to synthesize thecomponents adaptively selected in the synthesis process.

When, for example, the “scalable” is designated as the attribute of thecomponents to be synthesized for the composite component group in thisexample, a base stream transmitted via broadcast and an extended streamtransmitted via communication are synthesized. For example, when the“3D” is designated as the attribute for the composite component group, aright-eye image transmitted via broadcast and a left-eye imagetransmitted via communication are synthesized.

The example in which there is a plurality of “CompositeComponentGroup”elements has been described. Note that, however, when there is only a“CompositeComponentGroup” element, the optimal component is adaptivelyselected from the components to be adaptively selected in the loweradaptive layer in the composite layer as necessary. Alternatively, whenthere is only a component to be adaptively selected in the adaptivelayer, the component is constantly selected.

When the optimal component is selected in the process in step S402, theprocess goes to step S403. In step S403, the video output unit 413displays the image corresponding to the video and caption componentsselected in the process in step S402 on the display. In step S403, theaudio output unit 415 outputs the voice corresponding to the audiocomponents selected in the process in step S402 from the loudspeaker.When the process in step S403 is completed, the reception process inFIG. 15 is completed.

The reception process has been described above. In reception process,the optimal component is selected from a plurality of componentcandidates that can be received via broadcast or communication inaccordance with the control signal (the signaling information in FIG. 2)and presented. This enables the user to watch and listen to the imageand voice corresponding to the optimal component selected from thecomponent candidates that can be received, for example, when the userselects the channel of a desired television program.

4. Specific Example of Operation

A specific example of the operation that the broadcast communicationsystem 1 using the present invention can implement will be describednext.

(1) Multi-View Display Service

In the broadcast communication system 1, the transmission device 10transmits a broadcast component and the distribution server 30distributes a communication component. Thus, the reception device 40displays a first image via broadcast on the main view, and displays asecond image via communication on the sub-view. This enables amulti-screen display or a full-screen display of a selected image.

(2) Multilingual Voice and Caption Service

The distribution server 30 distributes a foreign language, such asSpanish, voice or caption (audio or caption component) via the network90 for a television program via broadcast (video and audio components)transmitted from the transmission device 10. This enables the receptiondevice 40 to output the foreign language voice or superimpose anddisplay the foreign language caption in synchronization with the imageof the television program.

(3) Sign Language Image Distribution Service

The distribution server 30 distributes a sign language image (videocomponent) via the network 90 for a television program via broadcast(video and audio components) transmitted from the transmission device10. This enables the reception device 40 to display the sign languageimage on a sub-screen on the image of the television program.

(4) Broadcast and Communication Switch Service

While the user watches a television program via broadcast (video andaudio components) transmitted from the transmission device 10 on thereception device 40, the distribution server 30 distributes a program(video and audio components) related to the television program via thenetwork 90 in response to the user's selection operation. This enablesthe user to watch the related program on the reception device 40. Notethat a plurality of communication components is prepared and one of thecommunication components is adaptively selected depending, for example,on the congestion of the communication channel. This selectionimplements adaptive streaming distribution. When the related program viacommunication ends, the display is returned to the television programvia broadcast.

(5) CM Insertion Service

When a television program via broadcast (video and audio components)transmitted from the transmission device 10 is switched to a commercialmessage (CM) while the user watches the broadcast television program onthe reception device 40, a CM (video and audio components) in accordancewith the information about the user's taste is provided from thedistribution server 30 via the network 90. This enables the user towatch a CM specialized for the user (Personalized CM). When the CMspecialized for the user via communication ends, the display is returnedto the television program via broadcast.

(6) Ultra High Definition Television (UHDTV) Compatible Service byHybrid Distribution

For example, in order to provide an image at 4K resolution, it isassumed that the transmission device 10 transmits via broadcast anencoded signal of an image at 2K resolution (video component) as a basestream and the distribution server 30 distributes an encoded imagesignal (video component) corresponding to the difference between theimage at 4K resolution and the image at 2K resolution as an extendedstream via the network 90. When the reception device 40 is compatiblewith 4K resolution in this example, the reception device 40 cansynthesize the base stream transmitted via broadcast and the extendedstream transmitted via communication and display the image at 4Kresolution. Note that, when the reception device 40 is not compatiblewith 4K resolution, the reception device 40 displays the image at 2Kresolution using only the base stream transmitted via broadcast.

Similarly, in order to provide an image at 8K resolution, an encodedsignal of an image at 4K resolution (video component) is transmitted asthe base stream transmitted via broadcast and an encoded image signal(video component) corresponding to the difference between the image at8K resolution and the image at 4K resolution is transmitted as theextended stream transmitted via communication. This enables thereception device 40 compatible with 8K resolution to synthesize thestreams and display the image at 8K resolution. On the other hand, whenthe reception device 40 is not compatible with 8K resolution, thereception device 40 displays the image at 4K resolution using only thebase stream transmitted via broadcast.

In order to provide an image at frame rate of 120 p, an encoded signalof a 60 p image (video component) is transmitted as the base streamtransmitted via broadcast and an encoded image signal (video component)corresponding to the difference between the 120 p, image and the 60 p,image is transmitted as the extended stream transmitted viacommunication. This enables the reception device 40 compatible with theframe rate of 120 p, to synthesize the streams and display the image atthe frame rate of 120 p. On the other hand, when the reception device 40is not compatible with the frame rate of 120 p, the reception device 40displays the image at the frame rate of 60 p, using only the base streamtransmitted via broadcast.

(7) Voice Combination Service

A language variation voice, a main or explanatory voice, and anothercontent variation voice (audio components) are transmitted from thetransmission device 10 or are distributed from the distribution server30 via the network 90 for a television program via broadcast (video andaudio components) transmitted from the transmission device 10. Thisenables the reception device 40 to mix and provide the voices inresponse to the user's selection operation.

(8) Adaptive Streaming Distribution Service Across Broadcast andCommunication

In the broadcast communication system 1, the transmission device 10transmits a component or a plurality of components, and the distributionserver 30 distributes a component or a plurality of components via thenetwork 90. The reception device 40 adaptively selects one of thebroadcast and communication components and can provide an image with aquality as high as possible. For example, the transmission device 10transmits an image at 2K resolution (video component) while thedistribution server 30 distributes an image at 4K resolution (videocomponent) via the network 90. This enables the reception device 40 toimplement the adaptive streaming distribution across broadcast andcommunication, for example, by basically displaying the image at 4Kresolution via communication and displaying the image at 2K resolutionvia broadcast that the reception device 40 can stably receive dependingon the congestion of the network 90.

5. Computer Configuration

The sequence of processes described above can be performed with hardwareor software. When the sequence of processes is performed with software,the program of the software is installed on a computer. The computer is,for example, a computer embedded in dedicated hardware, or ageneral-purpose computer capable of executing various functions byinstalling various programs.

FIG. 16 is a block diagram of an exemplary configuration of the computerhardware that performs the sequence of processes with the programs.

In a computer 900, a Central Processing Unit (CPU) 901, a Read OnlyMemory (ROM) 902, and a Random Access Memory (RAM) 903 are connected toeach other via a bus 904. Additionally, an input and output interface905 is connected to the bus 904. An input unit 906, an output unit 907,a recording unit 908, a communication unit 909, and a drive 910 areconnected to the input and output interface 905.

The input unit 906 includes, for example, a keyboard, a mouse, and amicrophone. The output unit 907 includes, for example, a display, and aloudspeaker. The recording unit 908 includes, for example, a hard diskor a non-volatile memory. The communication unit 909 includes, forexample, a network interface. The drive 910 drives a removable medium911 such as a magnetic disk, an optical disk, a magneto-optical disk, ora semiconductor memory.

The computer 900 having the configuration described above performs thesequence of processes, for example, by causing the CPU 901 to load theprogram stored in the recording unit 908 onto the RAM 903 via the inputand output interface 905 and the bus 904 and execute the loaded program.

The program that the computer 900 (CPU 901) executes can be providedafter being recorded in the removable medium 911, for example, as apackage medium. Alternatively, the program can be provided via a wiredor wireless communication medium such as a Local Area Network, theInternet, or digital satellite broadcast.

The computer 900 can install the program via the input and outputinterface 905 onto the recording unit 908 by attaching the removablemedium 911 to the drive 910. The program can be received with thecommunication unit 909 via a wired or wireless communication medium andinstalled onto the recording unit 908. Alternatively, the program canpreviously be installed on the ROM 902 or the recording unit 908.

Note that the program that the computer 900 executes can be a programthat chronologically performs the processes in the order describedherein, or a program that performs the processes in parallel, or at atime when the execution is necessary, for example, when the program isinvoked.

Each process step that describes the program that causes the computer900 to perform each process is not necessarily executed chronologicallyin the order illustrated as the flowchart, and the processes includeprocesses performed in parallel or individually (for example, parallelprocessing or processing by the object) herein.

The program can be executed by a computer, or by a plurality ofcomputers in decentralized processing. Alternatively, the program canalso be executed after being transferred to a remote computer.

The system is a collection of a plurality of components (for example,devices, or modules (parts)) herein. It does not matter if all of thecomponents are housed in a housing. Thus, each of the devices housed indifferent housings and connected via a network, and an apparatus inwhich the modules are housed in a housing is a system.

Note that the embodiments of the present invention are not limited tothe embodiments described above, and can variously be changed withoutdeparting from the gist of the present invention. For example, thepresent invention can be the configuration in the cloud computing inwhich a function can be shared by a plurality of devices and performedby the cooperation of the devices via a network.

Each step described in the flowcharts can be performed by a device orshared and performed by a plurality of devices. When a step includes aplurality of processes, the processes in the step can be performed by adevice or shared and performed by a plurality of devices.

Note that the present invention can have the following configuration.

(1) A reception device including:

a first reception unit that receives a component transmitted on abroadcast wave;

a second reception unit that receives a component distributed via anetwork; and

a control unit that controls operation of each unit,

wherein the control unit selects an optimal component from a pluralityof components that the reception device is able to receive.

REFERENCE SIGNS LIST

-   1 Broadcast communication system-   10 Data providing server-   20 Transmission device-   30 Distribution server-   40 Reception device-   201 Component obtaining unit-   202 Control signal obtaining unit-   203 Mux-   204 Transmission unit-   301 Control unit-   302 Component obtaining unit-   303 Accumulation unit-   304 Communication unit-   402 Tuner-   403 Demux-   404, 405, 406 Selection and synthesis unit-   407 Control unit-   408 NVRAM-   409 Input unit-   410 Communication unit-   411 Demux-   412 Video decoder-   413 Video output unit-   414 Audio decoder-   415 Audio output unit-   416 Caption decoder-   421 Reception buffer-   90 Network-   900 Computer-   901 CPU

1. A reception device comprising: a receiver receiving first, second,and at least another component belonging to one of at least twocategories including audio and video; a control circuitry configured tocontrol operation of the receiver, wherein in a third layer, the controlcircuitry is configured to select the first component or the secondcomponent as a first selected component, in a second layer, the controlcircuitry is configured to synthesize the first selected component inthe third layer and a component not selected in the third layer into asynthesized component, in a first layer, the control circuitry isconfigured to select a component selected in the third layer or thesynthesized component as a selected component for the one of the atleast two categories, and the control circuitry is configured to outputthe selected component for the one of the at least two categories to arendering device.
 2. The reception device of claim 1, wherein the firstcomponent is a broadcast component and the second component is acommunication component.
 3. The reception device of claim 2, wherein inthe third layer, the control circuitry selects a component at a bit ratefrom the first component and the second component at different bit ratesdepending on variations in Carrier or Noise (C/N) of a broadcast signalincluding the first component or congestion of a communication channelcarrying the second component.
 5. The reception device of claim 3,wherein the selected component in the third layer is a base layer andthe component not selected in the third layer is an extended layer. 6.The reception device of claim 3, wherein in the first layer, the controlcircuitry selects the first category component in accordance withthroughput of the reception device.
 7. The reception device of claim 2,wherein components in different categories are linked to each other witha view tag.
 8. A method comprising: receiving, by a receiving device,first, second, third, and fourth components, wherein the first andsecond components belong to a first category and the third and fourthcomponents belong to a second category; in a third layer, selecting, bythe receiving device, the first component or the second component as afirst selected component, in a second layer, synthesizing, by thereceiving device, the first selected component in the third layer and acomponent not selected in the third layer into a synthesized component,in a first layer, selecting, by the receiving device, a componentselected in the third layer or the synthesized component as a firstcategory component, and selecting, by the receiving device, the firstcategory component and selecting a second category component from thesecond category, the second category component being selected byperforming at least one of selection or synthesis of the third componentand the fourth component.
 9. The method of claim 8, wherein the firstcomponent is a broadcast component and the second component is acommunication component.
 10. The method of claim 9, wherein in the thirdlayer, a component is selected at an optimal bit rate from the firstcomponent and the second component at different bit rates depending onvariations in Carrier or Noise (C/N) of a broadcast signal including thefirst component or congestion of a communication channel carrying thesecond component.
 11. The method of claim 9, wherein the selectedcomponent in the third layer is a base layer and the component notselected in the third layer is an extended layer.
 12. The method ofclaim 9, wherein in the first layer, the first category component isselected in accordance with throughput of the receiving device.
 13. Themethod of claim 8, wherein components in different categories are linkedto each other with a view tag.
 14. A non-transitory computer readablemedium including executable instructions, which when executed by acomputer cause the computer to execute a method in a receiving device,the method comprising: receiving, by the receiving device, first,second, third, and fourth components, wherein the first and secondcomponents belong to a first category and the third and fourthcomponents belong to a second category; in a third layer, selecting, bythe receiving device, the first component or the second component as afirst selected component, in a second layer, synthesizing, by thereceiving device, the first selected component in the third layer and acomponent not selected in the third layer into a synthesized component,in a first layer, selecting, by the receiving device, a componentselected in the third layer or the synthesized component as a firstcategory component, and selecting, by the receiving device, the firstcategory component and selecting a second category component from thesecond category, the second category component being selected byperforming at least one of selection or synthesis of the third componentand the fourth component.
 15. The non-transitory computer readablemedium of claim 14, wherein the first component is a broadcast componentand the second component is a communication component.
 16. Thenon-transitory computer readable medium of claim 15, wherein in thethird layer, a component is selected at an optimal bit rate from thefirst component and the second component at different bit ratesdepending on variations in Carrier or Noise (C/N) of a broadcast signalincluding the first component or congestion of a communication channelcarrying the second component.
 17. The non-transitory computer readablemedium of claim 15, wherein the selected component in the third layer isa base layer and the component not selected in the third layer is anextended layer.
 18. The non-transitory computer readable medium of claim15, wherein in the first layer, the first category component is selectedin accordance with throughput of the reception device.
 19. Thenon-transitory computer readable medium of claim 14, wherein componentsin different categories are linked to each other with a view tag.